From 70286d59f1bd413009c28dea22ab69649fa87490 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 13 Mar 2026 00:51:14 +0100 Subject: [PATCH] avcodec/exr: Check input space before reverse_lut() Fixes: use of uninitialized memory Fixes: 490707906/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_EXR_DEC_fuzzer-6310933506097152 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/exr.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/libavcodec/exr.c b/libavcodec/exr.c index a0f00a7cf1..c7fcd302cd 100644 --- a/libavcodec/exr.c +++ b/libavcodec/exr.c @@ -637,6 +637,9 @@ static int piz_uncompress(const EXRContext *s, const uint8_t *src, int ssize, max_non_zero - min_non_zero + 1); memset(td->bitmap + max_non_zero + 1, 0, BITMAP_SIZE - max_non_zero - 1); + if (bytestream2_get_bytes_left(&gb) < 4) + return AVERROR_INVALIDDATA; + maxval = reverse_lut(td->bitmap, td->lut); bytestream2_skip(&gb, 4);